DLE 60cc Twin break in question
 

I have a question concerning breaking in a DLE 60cc twin.
The instructions state that the engine be mounted on a aircraft or a test stand with an appropriate shock absorber.
Product Manual #1 (PDF, 600 KB)
" During the break-in period, it is recommended that the engine be installed on the aircraft or a test stand with an appropriate shock absorber. Otherwise it is probable that vibration could rebound back to the engine and serious damages may occur during the break-in period. Break-in should be considered about the first 3-5 gallons you run in the engine. "

I don't yet have an aircraft built of that size. What would be an appropriate mounting for the engine sans an aircraft? I have read on the forums that some manufactures will void the warrenty if a gas engine is soft mounted. Am I correct about not soft mounting a gas engine?

Bought the engine for a Andy Sheber Pitts s1s.

Ken

The best thing you can do is mount it on the airplane ( with the wings mounted ) and fire it up. Get the needles adjusted to the point where you have a reliable idle, good transition to full power and slightly rich on the top end. Then go fly the engine and make small adjustments based on what was observed while in flight. What they are warning you about is mounting the engine too rigidly and setting up a destructive resonance. Personally I have flown every single gasoline engine I have ever owned on its first tank of gas.

Then that is what I will do. Haven't even started the plane build yet. Hopefully about mid year.

Thanks
Ken

+1

I would add to that, but not as a 'must do', is the installation of Bowman/BjornBaal rings as well. The engine will bed in quicker, and run better over the ling term with a set of those. My personal experience with them (in a DLE30cc, DLE55RA and an RCGF 70 Twin) is that they do run better, bed in quicker and generally perform a little better than stock rings. Its very easy to shove a set in before starting the engine. There are some divided opinions on them, but mostly positive results.

The only 'must do' for me, is to throw the spark plugs that it comes with, in the bin, and put some NGK's in it.

keep the engine a little rich during break-in, and I use 32:1 oil ratio and after a few tanks, change that to 40:1 and you will be golden.

Again, agree with the above. I'd repeat the Bjorn rings are not required but certainly desirable. The engine will run just fine with the stock rings but the break in time will be extended. The last two DLE engines I bought came with NGK plugs in the DLE sealed box so if the engine is fairly new, you may already have them.

DLE engines aren't the only engines that benefit from using Bjorn's rings. I've used them is several other expensive name brand engines with results the same as when installed in the Chinese engines. When the Chinese engines first made their appearance in the US market, the rings were extremely hard and not always quite round. Cylinder walls were also less than desirable and the combination made for an engine that seemingly took forever to break in. These days the Chinese rings and cylinders are very much improved but their rings still take longer to break in (bed in as some say) than when a Bjorn ring is used. A very worth while addition to the engine but keep in mind, this voids the warranty unless installed by someone like Valley View RC that installs them in new engines as an option.